Tail-skid and rudder for airplanes



y 30, 1933- .J. EJYOUNGER 1,911,416

TAIL SKID AND RUDDER FOR 'AIRPLANES Fi led June 17, 1932 Z'SheetS-Sheet 1 ATTORNEYS.

I 'I'NVE-NTOR;

' May 30, 1933. 1. E. YouN-GER 1,911,416

TAIL SKID AND RUDDEH FOR AIRPLANES Filed June 17, 1962 2 Sheets-Sheet 2 ATTORNEYS.

Patented May 30, 1933 UNITED. STATES PATENT OFFICE JOHN E. YOUNGER, 0F BERKELEY, CALIFORNIA, ASSIGNOR OF ONE-HALF TO CAPELIS SAFETY AIRPLANE CORPORATION, LIMITED, OF EL CERRITO, CALIFORNIA, A COR- PORATION OF CALIFORNIA TAIL-SKID AND RUDDER FOR AIRPLANES Application filed June 17,

This invention is a tail-skid and rudder for airplanes and is specifically directed to a retractable tail-skid which is retractable within the rudder, and is also directed to a specific type of rudder which concludes the streamline form of the tail of an airplane.

Tail-skids, as now applied to airplanes, consist either of the shoe or the wheel variety which are usually mounted adjacent to the tail end of the airplane, ahead of the rudder. This invention contemplates the mounting of the tail-skid in or on the rudder, whereby the tail-skid is operable in line with the rudder.

The main object of the invention, therefore, is to provide a rudder for airplanes, which, in addition to forming the guiding means for lateral shift of the airplane, also provides a continuation of the streamline form of the fuselage, and which also provides a housing for a retractable tail-skid.

Another object of the invention is toprovide a special wheeled tail-skid which may be retracted within, and supported by, the rudder.

A further object of the invention is to provide means for retracting and projecting the tail-skid from an opening in the bottom of the rudder, the operation of which is controlled from the cockpit.

- A still further object of the invention is to provide the retracting and projecting means with means which will automatically stop the movement of the tail-skid in either direction when the terminus of travel has been reached, and also providing means for automatically reversing the driving means when either terminus has been reached, so that by means of the control in the cockpit, the operation of the means will be alternately projecting and retracting each time the control in the cockpit is manipulated.

Other objects and advantages of the invention will become apparent as the followingdescription is read on the drawings forming a part of this specification and in which similar reference characters are used 1 to designate similar parts throughout the several views, of which:

Fig. 1 is a fragmentary view of the tail 1932. Serial No. 617,726.

Fig. 5 is a fragmentary sectional elevation through the invention, clearly. indicatingrthe operating means for the tail-skid.

ig. 6 is a section taken on line 6-6 of Fig. 5. I

Fig. 7 is a wiring diagram of the controlling means for the motor.

The rudder consists of an upper or guiding portion 10 which is made comparatively narrow in cross section as is indicated in Fig. 4, and a housing or terminal section 11, which portion is formed as a continuation of the tail 12 of an airplane as is clearly indicated at 13, 14 and 15. The rudder is pivotally mounted as is indicated at 16 and 17 in suitable brackets '18, which are secured to the tail end of the airplane. The rearward portion of the rudder is arcuately formed as is shown at 19 and is provided.

the rudder terminating in a point 21.

The inner structure of the rudder consists of a framework formed of a plurality of ribs 22 which are suitably secured together by means of the side walls 14 and 15 or by means of separate or individual webs as may be desired. The upper portion 10 of the rudder is made with sufiicient clear space to receive the operating mechanism for the tail-skid, while the lower portion 11 is made sufficiently large to receive the tail-skid wheel 23. I

. Pivotally mounted in axial alignment with the pivots 16 and 17 is a screw 24, which is supported in bearings 25. The screw 24 has fixedly secured thereon a bevel. gear 26 which meshes with a bevel gear 27 which is fixed on a shaft 28 which shaft .is driven by a motor 29 and which motor is suitably supported within the tail of the airplane as indicated at 30.

This motor may readily be mounted within the rudder if so desired, the bevel gear '26 being then mounted at the top of the,

screw 24, adjacent the bearing 25 and will then operate in the same manner. As is indicated in the drawings, with the hook-up shown, the bevel gear 26 extends through the back wall'19 of the rudder and due to the fact that the screw 24 is mounted in axial alignment with the pivots 16 and '17, swinging of the rudder Wlll have noefi'ect op the proper meshing of the gears 26 and 2 pivot 37, forming a hinged joint at this point, the other end of the yoke being pivoted at 39 to a bracket 40, which is fixedly secured to the rudder walls.

The controlling means consists of two spaced apart levers 41 and 42 which are pivoted at 43 and connected together by means of the connecting rod 44, this connecting rod cooperating with a reversing switch 45, the levers 41 and 42 coincidently operating two three-way circuit breaking switches.

The operation of the device is as follows:

With the tail-skid in the position shown in Fig. 5 and the terminals 46 and 47 suitably connected to a source of suitable electric potential, and with all connections made as shown in Fig. 7, which will be assumed to be correct for retractive movement of the tail-skid, switch 48 being manually moved to contact 49 as is shown, the circuit through motor 29 is completed from line 46 through switch lever 50, wire 51, wire 52, switch lever 48 to contact 49, wire 53, switch lever 54, wire 55, wire 56 to motor 57, and thence to line 47, and coincidently to contact 58 on the reversing switch to contact 59, thence through motor field winding 60, contact 61 to 62, and thence to 47. As the nut 31 moves upward and comes in contact with lever 41, switch levers 50 and 54 are moved to contact respectively with contacts 63 and 64, and coincidently, through movement of the connecting rod 44, the reversing switch is caused to bridge the gap between contacts 58 and 65, and, 62 and 66, breaking the circuit between 58 and 59 and, 62 and 61, thereby reversing the circuit through the field winding 60. This leaves the circuit broken between wire 52 and contact 67, the tail-skid being fully retracted, the motor reversed, and the circuit broken.

To project the tail-skid, lever 48 is moved over to contact 67, which completes the cir cuit from 46 through 50 to 63, from 67 through 48, 52 to contact 64, switch lever 54, wire 55, contact 58 to 65, and then in reversed direction through. the field winding 60, thence to 66, to 62 and thence to 47, the direction of the current through motor 57 not having been changed.

The tail-skid is shown in its retracted position by dotted lines in Fig. 5, and in its projected position by solid lines. It will be noted that due to the specific arrangement ofthebevel gears, that swinging of the rudder will not have any effect on the operation of the retracting mechanism. The switch levers 50 and '54 respectively may have the pivot points connected to the pivots 43 on levers 41 and 42, thesepivot points being indicated by the same numeral in Fig. 7.

Having described an operative device and method of operation, it will be understood that variations in construction and arrangement of parts which are consistent with the appended claims may be resorted to without detracting from the spirit or scope of the invention or sacrificing any of the advantages thereof.

I claim:

1. In combination with an airplane; a rudder having a screw in axiale alignment with the pivots of said rudder and a nut on said screw, a hinged strut and a tail-skid comprising a road wheel pivotally mounted at the hinged joint in said hinged strut, one end of said strut being pivotall secured in fixed position, the other end 0 said struts being pivotally secured to said nut, and means for driving said screw for retraction and projection of said tail-skid.

2. A rudder for an airplane comprising a guiding portion of comparatively narrow cross-section terminating in a point, and a housing portion of stream-line form, a retractable tail-skid mounted in said rudder, means for retracting said tail skid within said housing portion.

3. A rudder for an airplane comprising a guiding portion, and a housing portion of stream-line form, a retractable tail-skid comprising a road wheel and a hinged support therefor, mounted in said rudder and adapted to be projected therefrom, power. means for retracting and projecting said tail-skid, said power means being automatically controlled by the final projecting and retracting movements of said tail skid;

4. A rudder for an aeroplane comprising a guiding portion and a housing portion of and means for automatically making the power means inoperatlve and means for automatically reversing the direction of motion of said power means coincidently with the final retracting and projecting movements of said tail skid.

5. Means for retracting and projecting a tail skid, comprising two pair of hingedly connected struts, a vertically mounted screw, a nut on said screw, one pair of struts being pivotally connected to said nut, the other pair of struts being pivotally connected to a stationary member, ing said screw, means for automatically reversing the direction of rotation of said screw at opposite terminals of travel of said nut and means for automatically stopping said screw at opposite terminals of travel of said nut, and manually operated means for starting said power means.

6. In combination With a pivotally mounted rudder, having a housing formed in the lower portion thereof and an opening in the bottom of said housing; a screw rotatably mounted in'axial alignn'lent with the pivotal mounting of said rudder, a nut on said screw, a bevel gear fixed on said screw, an intermeshing bevel gear and a shaft therefor mounted externally of said rudder and a motor for driving said shaft, two forkedstruts hingedly connected at. their forked ends by means of a pivot and a road wheel on said pivot, a shock absorber in one strut, said one strut being pivotally connected to said nut, the other strut being pivotally connected to said rudder 1n fixed position,

means cooperating with said nut at opposite terminals of travel for automatically reversing the direction of rotation of said motor and for automatically breaking circuit to said motor, and manually controlled means for making circuit to said motor.

In testimony whereof I afiix my signature.

JOHN E. YOUNGER.

)OWBI' means for rotat- 

